Automatic core setters for centrifugal pipe casting machines



1965 G. o. BERNHARDT 3, 68,765

AUTOMATIC CORE SETTERS FOR CENTRIFUGAL PIPE CASTING MACHINES Filed June8, 1962 3 sheets sheet 1 INVENTOR GERD O. BERNHARD'T 9, 1965 5. o.BERNHARDT 3, 6 ,765

AUTOMATIC CORE SETTERS FOR CENTRIFUGAL PIPE CASTING MACHINES Filed June8, 1962 3 Sheets-Sheet 2 use.

INVENTOR GERD O. BERNHARDT Filed June 8, 1962 FIG.3

AUTOMATIC CORE SETTERS FOR CENTRIFUGAL PIPE CASTING MACHINES 3Sheets-Sheet 3 F" T F F \O s? r l 8 v ii if if Q ii e "3 d, I H

INVENTOR GERD O. BERNHARDT A'ITORN EYS United States Patent 3,168,765AUTOMATIC CORE SETTERS FOR CENTRIFUGAL FEE CASTING MACHINES Gerd 0.Bernhardt, Pointe Claire, Quebec, Canada,

assignor to Canada Iron Foundries Limited, Montreal, Quebec, CanadaFiled June 8, 1962, Ser. No. 201,078 Claims priority, applicationCanada, Mar. 21, 1962,

844,807 3 Claims. (Cl. 2265) This invention relates to automatic coresetters for centrifugal pipe casting machines and basically known in thetrade as Delavaud machines. These generally embody cylindrical metalwater-jacketed molds mounted for rotation within a carriage which imoved axially along an inclined bed or trackway during the castingoperation. In this type of apparatus the carriage moves longitudinallyrelatively to a pouring trough through which molten metal is suppliedfirst of all to the bell end of the pipe mold and then continuouslyalong the length of the mold as it moves, the pipe being formed bycentrifugal action achieved by the rotating mold. When the mold reachesthe end of its longitudinal travel as finally to position the end of thetrough at the spigot end of the pipe mold and when the complete pipe hasbeen cast, the carriage comes to rest and the pipe is extractedtherefrom at the bell end of the mold. Prior to its return to theopposite end of its runway for the next casting operation, it isnecessary for an operator to insert a bell core in the bell end of themold and to wedge and lock it in position as to provide for the initialformation of the bell end of the pipe at the commencement of the nextcasting operation. Similarly when the pipe is cast and the mold reachesthe end of its travel as above referred to, the operator first of allremoves the core holding ring prior to withdrawal of the cast pipe fromthe mold. Most of these two manual operations are eliminated by the present invention.

While pipe casting operations on machines of this kind may beaccomplished in a two-stroke cycle as above according to more recentdevelopments in this field, the

older mode of operation required four cycles: (1) a down stroke duringwhich the pipe is cast when the operator removes the core for theextracting operation and an expanding grabbing device is introduced tothe bell end of the pipe to cause withdrawal of the pipe from the moldas the mold is caused (2) to move back up the track to its originalpro-casting position and wherein the pipe leave the mold, is received oncarriers and moved transversely from the carriage path, whereupon (3)the carriage is moved back down to its final casting position so thatthe operator may insert a new core and (4) then is moved up the track topre-casting position for the commencement of another casting operation.In other words, after the extraction of the pipe it is necessary to movethe carriage twice between casting operations, i.e. a down stroke sothat the operator may place the core and an up stroke to place the moldback in the position for the casting operation. To convert suchfour-cycle machines to two-cycle machines, using a travelling extract-oras has been developed the last few years, requires an increase in theamount of working space with attendant high cost in terms of conversion,whereas such space may not be available. In other words, in many casesconversion may be impossible in a plant already designed I and inoperation on four-cycle principle.

The present invention provides a simple means wherebyfour-cycle machinesof the kind described may be converted readily to two-cycle strokemashines by pro viding an automatic core setting means operable afterthe pipe has been extracted and during the return travel of the carriagetowards pre-casting position as to eliminate the two interveningoperation cycles, i.e. the extra stroke of the carriage back to thecasting position for core setting purposes and its return to pre-castingposition for the next casting operation. It also eliminates some of themanual core setting functions and which can be applied if desired withadvantage to the improved type of two-cycle casting machines. Overall inparticular, however it will be obvious that the invention has its majoradvantage in the material increased production by its capacity ofsimpleconversion of four-cycle type machines to two-cycle type, thus achievinga marked advance in this particular art.

The invention will be clearly understood by reference to the followingdetailed specification taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is an enlarged perspective illustration of automatic core settingmeans according to the present invention mounted in conjunction with thebell end of the pipe mold carried in a centrifugal casting machine andshowing the core setting device in a position to move the core into thebell end of the mold.

FIG. 2 is an enlarged fragmentary top plan view partly in longitudinalsection of that end of the mold shown in FIG. 1 and illustrating thecore moved into position within the bell end of the mold; and

FIGS. 3 to 6 are top plan schematic illustrations of the mold and coresetter in various positions of travel of the mold carriage during thecasting of a pipe.

Referring to the drawings, A indicates a carriage containing a rotarypipe casting mold, which carriage in well known manner is adapted to bereciprocated on a trackway 10 from an initial precasting position to afinal casting position and wherein the pipe is cast during travel of themold and carriage to final casting position. In FIGS. 3 to 6, thecarriage is shown, respectively, in final casting position (FIG. 3)where the pipe is about to be extracted from the mold; .pre-castingposition (FIG. 4); during casting (FiG. 5) where a casting is just aboutcompleted with the mold moving near to final casting position; and finalcasting position (FIG. 6) where extraction of the cast pipe iscommencing.

Referring again to FIG. 1, the bell end of the rotary mold 11 is shownopen for reception of the bell core after withdrawal of a pipe therefromand which is approximately the position illustrated in FIG. 6. Accordingto the invention, a movable bell core holder B is mounted on thecarriage for swinging movement relatively thereto and which maybeaccomplished as shown in FIG. '1 by means of the vertical hinge shaft 12carriedin suitable brackets on the mold carriage which swingably carriesa suitable lever such as the bell crank lever 13 rigidly fastened to arim 40 of the movable bell core holder B.

15 which is designed to receive the bore of the core C in frictionalfit. The core C is provided with the flanged base ring 16, the exteriorface of the flange thereof being tapered as at 17 to center inthe'frusto-conical opening 18 of the bell end of the mold 11. Theprotector sleeve 14 is secured .as shown to a driving plate 19 whichbacks the flanged base ring 16 of the bell core C and. is clampedtowards its outer end by suitable set screws 20 passing through therotary member or sleeve 21 of the bell core holder and which suitablycarries the rotatable portion 22 anearee of the roller bearing raceway23 which, together with the stationary portion 24, carries the rollerbearings 25 therebetween, the bearing assembly being closed withsuitable seals, as shown, in normal manner. The protector sleeve 14 maybe enclosed by the end casing 26 which is bolted to the stationary ringelement 27 to which the lever 13 is rigidly secured by means of theconnector arm 13a. Alternatively end casing 26 may be omitted to permitconstant inspection of the pouring operations.

Ring 27 has the annular fitting 28 rigidly fastened thereto, as bywelding, and which in turn is provided with the radially extendingflange 29 adapted slidably to receive the grooved adjusting ring 30having the radially extending groove 31 and which permits of the radialadjustment of ring 30, relatively to the annular fitting 28 and ring 27carrying it, so that the base plate 16 of the core will adjust to fitaccurately within the frusto-conical opening 18 of the bell end of themold. Since the movable and stationary parts of the core holder arecarried by the radial adjustment ring 30, it is clear that requiredlimited radial shifting of the bell core C and its flange ring 16 willbe achieved as the latter is being positioned within the opening 18 ofthe bell end of the mold.

The driving plate 19 is formed with a series of notches 32 in itsperiphery which are designed to register with and straddle suitabledriving pins 33 carried on the end of the rotary mold 11 so that whenthe swingable core holder B is swung, to position the core C within theopen bell end of the mold 11, the driving plate 19 will be placed 1noperative driving engagement with the drive pins 33. Consequently, therotatable parts of the core holder B are adapted to rotate with themold. It will be clear, therefore, that the movable core holder B can beswung to position the bell core accurately within the open bell end ofthe mold as to provide for commencement of casting.

The .swingable bell core holder B is designed to be actuated by anysuitable means, here shown (FIG. 1) as a pneumatic cylinder 34, which issuitably mounted on .the mold carriage A and has its piston rod 35pivotally connected to one end of bell crank lever 13. The pneumaticcylinder 34 is adapted to have air lines (not shown) connected theretoin well known manner and controlled by suitable well known valvemechanism so that the piston may be caused to reciprocate as required.

Upon completion of a pipe casting operation, the cylinder 34' isactuated to pull the bell crank lever 13 as to swing the bell coreholder B outwardly tothe position shown in FIG. 3, whereupon the pipemay be extracted from the mold and the operatorthen places a new bellcoreon the holder B. The carriage A is then retracted in well knownmanner on the trackway 10 from the position shown in FIG. 3 to theposition shown in FIG. 4 where the pouring trough 36 is disposed withinthe mold with its pouring spout located at the bell end of the mold.

" As it reaches this position, or just prior thereto, the cylinder 34 isactuated to push the bell crank lever 13 and locate and secure the bellcore within the previously open bell end of the mold 11. Pouring maythen commence in the normal manner with the carriage moving from theposition in FIG. 4 towards final casting position and during which timethe pipe is being cast by centrifugal action due to the rotation of themold. On completion of casting, as in FIG. 6, the cylinder 34 isactuated to cause the bell core holder B to swing outwardly and removethe core so that the extractor may be caused to enter and remove thepipe from the mold. The pipe is conveniently removed by introducing theexpanding pipe grabbing device 37 into the bell end of the pipe and asthe carriage A is retracted, the'pipe is extracted, received on suitablecarriers (not shown) and moved transversely out of the way, 'asgenerally illustrated in dotted lines in FIG. 4. Prior .to or duringextraction of the pipe, the operator will remove the core and ring, ifit still remains on the bell core holder B, and place a new bell coreand ring on the holder. Thus, when the carriage moves back to itspre-casting position as the pipe is extracted, the automatic insertionof the bell core in the bell end of the mold after extraction of thepipe provides for commencement of the next pouring operation. Pipecasting is thus achieved in a two-cycle operation of the apparatus ascompared to four-cycle operation previously necessary, in this type ofinstallation, wherein after extraction the carriage was moved back againto the final casting position so that the operator might insert andfasten a new core within the bell end of the mold whereupon the carriagewas moved back to pouring position. Thus without altering the four-cycletype installation in any way, such aninstallation is automaticallyconverted into a two-cycle operation with obvious increase inproduction.

The automatic core setting thus achieved while providing the primaryadvantage above described also achieves additional advantages since iteliminates the necessity for the operator to set a core in the bell endof the mold and fasten and wedge it as in past practice, as well as thenecessity of manually releasing said fastening means at the end of thecasting operation. Consequently, on newer two-cycle installations itwill prove of advantage as well but, primarily, as above indicated, itis of particular advantage in converting four-cycle installations intotwocycle without the necessity of increasing the space of operation andwhich is a requirement of two-cycle installations where the pipeextracting operation is achieved by an extractor operating on a longtrackway and which Withdraws" the pipe completely from the mold and awayfrom the carriage prior to the return of the carriage to pre-castingposition.

It is to be understood that the foregoing illustrates a preferredembodiment of my invention and which is identified in principle with acaptive movable bell core holder carried on a rotary pipe moldcontaining carriage employing controllable means for moving said bellcore to a position within the bell end of the pipe mold and withdrawingit therefrom at predetermined stages of operation of the pipe moldingapparatus. Consequently, changes may be made in the mounting andconstruction of the movable bell core holder including as well theshiftable core centering structure without departing from the spirit ofthe invention.

What I claim as my invention is:

l. in a centrifugal pipe casting machine employing a rotatable moldwithin a travelling carriage, a movable bell core holder adapted tocarry a bell core and swingably mounted on a hinge fixed to saidcarriage to one side thereof adjacent the end of the carriage, the axisof said hinge lying in a plane extending at right angles to thelongitudinal axis of said mold, controllable means for moving saidholder to position said core operatively within one end of said mold forcommencement of a casting operation and for moving said holder away fromsaid mold after completion of casting to permit axial withdrawal of thecast pipe from the. mold, said bell core holder having radiallyshiftable means supporting said core for centering said core accuratelywithin the open end of the mold.

2. The combination with a reciprocal carriage containing a rotary pipecasting mold, of a bell core holder jace'nt to that end of the carriagefrom which the bell end of the pipe mold is accessible, the axis of saidhinge lying in a plane extending at right angles to the longitudinalaxis of said mould, said holder being adapted to receive and carry abell core and being swingable towards the bell end of said mould tocenter said bell core and secure it within and closing said bell end ofsaid mold for casting purposes and swingable away from said bell end ofthe mold to permit withdrawal of the cast pipe therefrom, andcontrollable means operable at a predetermined time prior to casting andafter casting respectively for 6 References Cited by the Examiner UNITEDSTATES PATENTS 1,942,919 1/34 Enrich et a1. 2265 2,107,322 2/38 Andersonet a1. 2265 3,074,130 1/63 Wittmoser et a1. 22-65 MICHAEL V. BRINDISI,Primary Examiner. WILLIAM J. STEPHENSON, Examiner.

1. IN A CENTRIFUGAL PIPE CASTING MACHINE EMPLOYING A ROTATABLE MOLDWITHIN A TRAVELLING CARRIAGE, A MOVABLE BELL CORE HOLDER ADAPTED TOCARRY A BELL CORE AND SWINGABLY MOUNTED ON A HINGE FIXED TO SAIDCARRIAGE TO ONE SIDE THEREOF ADJACENT THE END OF THE CARRIAGE, THE AXISOF SAID HINGE LYING IN A PLANE EXTENDING AT RIGHT ANGLES TO THELONGITUDINAL AXIS OF SAID MOLD, CONTROLLABLE MEANS FOR MOVING SAIDHOLDER TO POSITION SAID CORE OPERATIVELY WITHIN ONE END OF SAID MOLD FORCOMMENCEMENT OF A CASTING OPERATION AND FOR MOVING SAID HOLDER AWAY FROMSAID MOLD AFTER COMPLETION OF CASTING TO PERMIT AXIAL WITHDRAWAL OF THECAST PIPE FROM THE MOLD, SAID BELL CORE HOLDER HAVING RADIALLY SHIFTABLEMEANS SUPPORTING SAID CORE FOR CENTERING SAID CORE ACCURATELY WITHIN THEOPEN END OF THE MOLD.